Thursday, June 21, 2007

One of my favorite things to do on the web is to go see the wonders of the world with Google Maps. Recently I read about this huge geoglyph of a man throwing a stick, known as the Marree Man. The geoglyph is located in South Australia and is very intriguing.

The Marree Man, or Stuart's Giant as it was named in anonymous press releases (after John McDouall Stuart), is a geoglyph discovered by air on 26 June 1998. The geoglyph appears to depict an indigenous Australian man, most likely of the Pitjantjatjara tribe, hunting birds or wallabies with a throwing stick. It lies on a plateau at Finnis Springs 60 km west of the township of Marree in central South Australia. It is just outside of the 200,000 square kilometre Woomera Prohibited Area. The figure is 4.2 km high with a circumference of 15–28 km. It is the largest known geoglyph in the world and is estimated to have taken between four and eight weeks to create, but despite this its origins are a mystery, with not a single witness to any part of the expansive operation.

The Marree Man is the largest manmade artwork in the world. The geoglyph depicts a man holding either a throwing stick once used to disperse small flocks of birds, or a boomerang (but see Plaque section below).

The lines of the figure were 20–30 cm in depth at the time of discovery and up to 35 metres in width. It was made with a 2.5 metre wide, eight-tine plough which was attached to a tractor, with the lines needing as many as 14 passes. The tractor would have had to have travelled an estimated 400 km and used up more than 300 litres of fuel.

A local pilot in the region, Brad Thompson, stated that the image had probably been defined by earthmoving machinery going over the lines of the figure at least sixteen times.

To select a suitable site, aerial photography or satellite imagery would have been needed. Using a computer, the figure could have been superimposed over the photograph and adjusted to fit the geography with the corresponding latitude and longtitude coordinates mapped out. Some surveying skills would have been needed to plot the outline, and then with the aid of a hand-held global positioning system stakes could have been placed every hundred metres or so.

The image is gradually eroding through natural processes, but because the climate is extremely dry and barren in the region, the image is still visible. While there is a layer of white chalk material slightly below the red soil, the figure was not defined to this depth. This has led to questions as to why the creators would not have dug a little deeper and made the image both more visible and more permanent.